Micronor Inc., Newbury Park, CA, offers MR338, an MRI-compatible fiber-optic absolute rotary encoder. The all-optical, nonmetallic passive sensor provides precision absolute angular measurement from 0° to 360° with 13-bit (8192-count) resolution plus 12-bit (4096-count) multiturn tracking . The encoder is designed for use in functional-MRI research, MRI teach phantoms, EMC test, and other electromagnetic environments where EMF and RF transparency is required. A duplex multimode fiber-optic link (up to 2500 m) connects the MR338 sensor to an MR330 controller installed outside the MRI area. The controller features multiple built-in interfaces including SSI, USB, RS-485, RS-232, Modbus RTU, digital and analog.